Friday, September 24, 2010

Dyno time!

Today we made the trip up to the dynojet dynometer at Dan Judy's Automotive in Salem, John in his 85 Vanagon TDI and me in my 93 Eurovan TDI. It was an action packed afternoon and finally we have some data points:
John's Van: 118hp and 245 ft/lb at the wheels running straight #2 D
Justin's Van: 110 hp and 213 ft/lb at the wheels running straight biodiesel (B99)

To be compared fairly with the posted power specs of the AHU engine (90hp & 155ft/lbs), which are measured at the crank, the rule of thumb is to add 15-20%. So now the numbers look a little more impressive and that fits with how they both drive down the road:

John's Van: 136hp and 282 ft/lb at the crank
Justin's Van: 126hp and 245 ft/lb at the crank

And here's the correction for biodiesel on my van (5-10% reduction in BTUs depending on feedstock, so we'll call it 7.5%) :
Justin's Van: 135hp and 263 ft/lb at the crank

Also worth noting is that peak HP and torque come on very early, right around 2500rpm, so all that power is there under foot at very low revs.

More pics of our rigs on the dyno:

Strapping down the Van to the dyno.

Yikes that's a smokey beast.

TDI Eurovan power curves, torque on top, HP on the bottom. The peak for the torque corresponds with around 2200rpm. Much smoother lines than the Vanagon graph above.

Dyno tech talk.

Soot scrawl behind the Vanagon after the smoke show.

My humble little 93 EV weekender strapped to the dyno.

Strapped, aligned and ready to roll!

Dyno time is fun time: not quite like fun family time, but quite like fun manly time.